Model output discussion - 5th December 2016 - Into Winter we go

[Nick F]

Again the GFS operational (18z) is progressive at pushing the N Atlantic block E/SE into western Europe much faster or contrary to GEFS and  EPS guidance - which keep the block to the W and NW.

Be interesting where tomorrow's operational rollercoaster takes us ...

[bluearmy]

12 minutes ago, Gael_Force said:

Thanks. I assume the 18z is showing a version of this with the very cold air coming west at a more southerly point.

Not a million miles away but too much mobility in the northern arm and the pattern far too suppressed south as a result. we're talking about uppers -20/-15 in the Low Countries, Germany, s uk 

[Banbury]

Control serving up something a tad different , LP bombing up towards the SE of Iceland

[Allseasons-Si]

^And to add  to that EES is that in the last few days i have noticed that the trajectory of these lows(forecast),to track NW-SE ,it will only be a matter of time one will POTENTIALLY slide more in a favorable position for us to get that holy grail,the ECM would/could get there and would of been nice to see a 268hrs chart

happy with the output tonight.

[Allseasons-Si]

And here she comes,bang on Que with the op the control is better though with more height's into Greenland and a separation of that shortwave in the mid Atlantic

 

 

[Nick F]

If anyone wanted a taste of how good the 12z EPS control was, Joe B has kindly posted a chart on twitter ... now imagine that trough undercutting the Griceland block and you get the picture

 

[Banbury]

Controls is certainly ok

[Allseasons-Si]

The control is very similar to the 12z post 240 hrs.

good consistency.

[nick sussex]

41 minutes ago, Nick F said:

Nick Sussex in the Pyrenees will be salivating over the 18z GFS FI, though he's not around recenty

Overall, a fairly cold run for the UK though, bar a brief warm up between the two northerlies.

I'm here! Been very busy with friends over for Christmas, those who enjoy my ramblings/ rantings/ occasional toys out of the pram can look forward to my proper return later on Saturday ! Yes I saw that GFS output but won't hold my breath that anything will see off the wretched Euro high until it's modeled within a decent timeframe. As for the ECM and it's nice day ten output the road to that looks very  complicated with those Atlantic lows yet another obstacle in what has seemed a month long assault course for coldies.

[Allseasons-Si]

-12 uppers encroaching the NE of BI in the latter stages.

choo! choo!

 

 

Edited December 28, 2016 by Allseasons-si

[Banbury]

ENS also looking good

P 1 (ish ) , 2 , 3 ( Belter ) , 4 ( ish later )  , 12 , 13 , 14 (ish ) , 15 , 17 , 18 ( lovely ) , 19 ( teasing Easterly later ) , 20

Some decent ones in that , only looked after 192 so well into FI , still plenty to play for.........................and be pleased about

[Allseasons-Si]

And ec ens are out and you can see the first black line i have drawn for the 3rd of Jan cold snap but some members keep it cold a few more days after,the red line represents a marked cluster not getting above 5c from the 7th and the second black line representing quiet a few members getting to -5 ,the ec is right in there at the end of the run(red line),so no outlier.

Edited December 29, 2016 by Allseasons-si
typo

[Daniel*]

1 minute ago, Banbury said:

ENS also looking good

P 1 (ish ) , 2 , 3 ( Belter ) , 4 ( ish later )  , 12 , 13 , 14 (ish ) , 15 , 17 , 18 ( lovely ) , 19 ( teasing Easterly later ) , 20

Some decent ones in that , only looked after 192 so well into FI , still plenty to play for.........................and be pleased about

Not much commentary no wonder  

Not nearly as good compared to 12z ENS a marked reduction in very cold runs especially in FI a quite apparent cluster going for something milder. The control is decidely on its own Allseasons.

I regret to inform you.  

[Banbury]

3 minutes ago, Changing Skies said:

Not much commentary no wonder  

Not nearly as good compared to 12z ENS a marked reduction in very cold runs especially in FI a quite apparent cluster going for something milder. The control is decidely on its own Allseasons.

I regret to inform you.  

Your mild bias is apparent , you really are nit picking my friend, they are a good set of runs . Snow %'s are very very similar. I certainly wont lose much sleep

Edited December 29, 2016 by Banbury

[Allseasons-Si]

11 minutes ago, Changing Skies said:

Not much commentary no wonder  

Not nearly as good compared to 12z ENS a marked reduction in very cold runs especially in FI a quite apparent cluster going for something milder. The control is decidely on its own Allseasons.

I regret to inform you.  

But that's well into fl CS,looks good to me,at least the control follows the op on this run

Edited December 29, 2016 by Allseasons-si

[Daniel*]

2 minutes ago, Banbury said:

Your mild bias is apparent , you really are nit picking my friend, they are a good set of runs .

Lol! that's the funniest thing I've heard all day. I'm a diehard coldie. Just saying it how it is, far from terrible indeed there are some good ones but evenly spread with some not good ones. 

[nick sussex]

I really hope the models don't manage to find a way to drag out the drama as I think it's high time something went right this winter. Looking at the upstream pattern and what NCEP expect with the progression in the USA the ECM does seem a better fit for that but I'd certainly not put a lot of money on its solution because of those troublesome Atlantic lows. The expectation of below normal temps across most of the Conus would tie in with the more amplified initial troughing which then progresses east so that high pressure lobe exiting Canada is likely to verify but it's the bit in between and how those Atlantic lows react to that downstream which is more complicated . The GEM and GFS ops do look a bit flat later on and would lift the cold out too quickly from parts of the USA.  I dont think we'll manage one of those 5 star Greenland highs, more likely is an initial high south Greenland which then topples towards Scandi as the upstream pattern progresses east and that's a decent fit for the negative EPO. I think  if we're to see some deeper cold it's likely  to have to come from the ne or east rather than north.

[Cheshire Freeze]

9 minutes ago, Changing Skies said:

Lol! that's the funniest thing I've heard all day. I'm a diehard coldie. Just saying it how it is, far from terrible indeed there are some good ones but evenly spread with some not good ones. 

You are indeed correct. I noticed as they were updating that the ensemble mean is not as 'sharp' as the 12z suite offered up. I hope we don't see an ECM flip tomorrow morning! It is usually a bad omen when the 18z op or ensemble suite go the opposite way to what we'd like with a lot of teeth gnashing and toys out of the pram the following morning upon the ECM's efforts!

Edited December 29, 2016 by CreweCold

[nick sussex]

5 minutes ago, CreweCold said:

You are indeed correct. I noticed as they were updating that the ensemble mean is not as 'sharp' as the 12z suite offered up. I hope we don't see an ECM flip tomorrow morning!

If the upstream pattern verifies then the UK would be incredibly unlucky not to manage something wintry out of that. Of course luck and the UK isn't in recent times a match made in heaven! If you get the initial amplified troughing in the USA then downstream you have to get the high exiting Canada, I think the issue is how far north that gets and then what the models do with those Atlantic lows.  The ECM might be a bit too amplified and the GFS and GEM ops too flat, a middle ground solution should still deliver something wintry. It would be great though if we could see the best outcome for a change.

[Cheshire Freeze]

13 minutes ago, nick sussex said:

 It would be great though if we could see the best outcome for a change.

Very rarely happens though does it?!

I'd love to know why the flatter outcomes shown are seemingly more likely to verify when there's a model stand off. There must be a reason.

[Brocken Spectre]

Sometimes I do wonder if too much staring into the tea leaves that is FI and looking for cold, that it's easy to forget (and enjoy) the current cold snap.
It's currently -2, superbly frosty and has been for 2 days.  Frost lasting all day in many parts.
  Indeed there is a chance of the fluffy stuff in the next week, also some great looking charts (in perspective to what's been before) but don't get so despondant as to miss the current "nice chilly  stuff". So much better that the last few years of wind, claggy skies and 10'c+ temps.

[Catacol]

2 hours ago, Changing Skies said:

Not much commentary no wonder  

Not nearly as good compared to 12z ENS a marked reduction in very cold runs especially in FI a quite apparent cluster going for something milder. The control is decidely on its own Allseasons.

I regret to inform you.  

Largest GFS cluster tonight maintains high pressure to the NW and a cold northerly air stream for the end of next week. Plenty of interest ongoing.

[Daniel*]

1 hour ago, Catacol said:

Hi Catacol,

I suppose I was using quite hyperbolic language while being on the cheeky side, it's hard to decipher that on a forum my apologies, it is never in my intent to provoke. I may have been a little hasty in forming a judgement nonetheless, what I contributed was not false, but the focus for once, was not on what most want to hear. It would be good if folk looked at both sides, rather than just focusing on the cold 'stuff', of course it's what most of us desire, but it is important to acknowledge. A small ember can grow into an inferno with the models.

It would be good folk never got snappy over such trivial matters. While I'm not disputing the interest, there is no real sign of deep sustained big freeze yet, perhaps I'm setting the bar too high. The 12z ENS excited many this set was clearly more 'muted' and it shouldn't be understated, albeit there is inconsistency in the long term, so it's not wise to fret over. The GEFS mean 500mb anomaly charts persist in keeping +ve heights to the north and west through pretty much the entirety and on the basis of that, you simply cannot ask for much more. It does appear undoubtedly we will see a reload of cold and it will not be the last, I think January has a lot going for it, we shall see as always.

Edited December 29, 2016 by Changing Skies

[Cheshire Freeze]

UKMO at day 6 doesn't follow the script this morning

GFS at day 6 a lot better than the UKMO as it maintains that wedge of heights between the LPs that Steve was talking about earlier

So...still no resolution to this one

 

[Ali1977]

6 minutes ago, CreweCold said:

UKMO at day 6 doesn't follow the script this morning

GFS at day 6 a lot better than the UKMO as it maintains that wedge of heights between the LPs that Steve was talking about earlier

So...still no resolution to this one

 

Lets hope the ECM backs the GFS or is even better. At day 6 that is a fair difference so one model will be left red faced!! By day 9 the GFS looks ok but that's a big wedge of PV over Greenland and Canada,  not as good as last nights runs.

Edited December 29, 2016 by Ali1977